There are many circumstances in which it is desirable to prevent tampering with information printed on a substrate. For example, various types of security features have been provided for various documents such as currency. With the advent of modern color copiers, various types of documents are readily counterfeited, with substantial resulting losses incurred by businesses. One area that has not been addressed from the standpoint of providing a security document which will evidence alteration of the document should printed information thereon be altered is the area of decals. More particularly and for example, decals are oftentimes used in the process of registering an automotive vehicle wherein a form, i.e., the registration, is provided the vehicle owner with an attached decal. The decal is removed from the form and applied to the vehicle license plate. Oftentimes, the use of decals applied to license plates indicate the payment of vehicle registration fees. Typically, the decals are printed with the state and year of registration or state and year of registration expiration. The printing process may include any one of a number of different processes wherein a toner receptive coating is overprinted on the decal substrate using laser, ion deposition, ink jet or other processes. However, it is recognized, for example, that laser-printed decals are relatively easy to modify by removing the toner and reprinting the necessary information such as the state and year date of registration expiration. Consequently, to avoid payment of additional registration fees for forthcoming years, individuals have been found to apply a solvent to the surface of the decal which removes the toner and, hence, the printing, enabling the decal to be reprinted without authorization. In the case of automobile license decals, many different types of solvents are readily available for removing the toner, such as gasoline, bleaches, alcohol, methylethyl ketone, toluene, turpentine or brake fluid. Any other strong solvent could typically remove the toner from the underlying substrate.